So I recently purchased a Globe Brush Cherry starter bonsai (litte tiny dude. Named him Kirsebær, Norwegian for cherry.). It is potted in a mixture of soil, pine bark, and lava rocks. It only gets approximately 1.5 to 3 hours of day where the sunlight is directly on him because of the way the houses in my neighborhood are positioned. I was watering him every two days and he was nice and green, but then suddenly the soil was super dry when I moved him out of the window for the night. I am a very scatterbrained person with add so it is possible I forgot to water him ( I read that not watering on schedule is a good idea. Bad for me because I need lists and schedules and alarms to do anything.) for an extra day. Will this hurt it? Some leaves seem kind crinkled up and dry/brown. I can grow anything else, but this whole bonsai thing seems to be a very sensitive thing. I am very nervous.

it should be fine having only one day without watering.
Look up watering guidelines at the top of the page.

bonsai is not so sensitive. Water when the pot gets dry. Do not water when wet. It is fairly simple, really

Joking aside.. It should be fine. As long as the leaves return to normal after you water, nothing has happened. If some of the leaves did not return, still no worries. If most of the leaves stay dry & crinkled.. You have a problem. Only solution.. Time. Do NOT keep the soil extra wet; Once roots really dry out, they partially die off. So the plant cannot take water as quickly as before. Keeping it extra wet will hamper the growth of new roots. So .. Unless there is sever damage: Do not worry. With severe damage: Keep out of direct sunlight untill you see buds starting to swell. With winter around the corner, the plant may decide to not grow new leaves this year..

Most of the leaves have returned to normal. Looking at it now, the only ones that appear to be truely dead/dry are the really new tiny leaves. Other than that, since ive watered it most of the leaves seem ok and some are even growing. Its summer here in Florida so I dont know if that affects what I should do.